TERT Mutation Is Accompanied by Neutrophil Infiltration and Contributes to Poor Survival in Isocitrate Dehydrogenase Wild-Type Glioma

Mutation of the telomerase reverse transcriptase (TERT) promoter has been demonstrated as an unfavorable prognostic marker in patients with isocitrate dehydrogenase wild-type (IDHwt) glioma. This study aimed to investigate the immune role of TERT promoter mutation status which could improve prognostic prediction in IDHwt. TERT mutation status, IDH mutation, and 1p-19q codeletion status data were obtained from 614 glioma cases from the Cancer Genome Atlas, and 325 cases from the Chinese Glioma Genome Atlas. The same information was obtained from 49 clinical glioma tissues. TERT mutation is preferentially present in glioblastoma and IDH-wt gliomas and is associated with poor prognosis. Moreover, TERT mutation was associated with infiltration of neutrophils and expression of neutrophil chemokines. which might partially contribute to the poor outcome in IDH-wt glioma. Furthermore, patients with IDH-wt glioma did not harbor increased peripheral neutrophils, implying that the infiltrated neutrophil in the tumor environment might due to cytokine chemotaxis. In this study, we hereby propose that TERT mutation might be a molecular driver of the dysfunctional immune microenvironment in IDH-wt glioma. TERT mutation may be a potential immune therapeutic target for optimizing treatment combinations and patient selection for glioma immunotherapy.

Clinician's modern approaches to molecular genetic diagnosis of glioblastomas

The article is devoted to the issue of molecular genetic diagnosis of cerebral glioblastomas. Despite significant advances in neurooncology, little progress has been made in prolonging the life of patients with cerebral glioblastoma, and a significant part of the effectiveness of treatment depends on the recognition of two prognostic biomarkers: mutations of the isocitrate dehydrogenase (IDH) promoter and the methylation of the O6-methylguanine methyl transferase (MGMT) promoter. The article summarizes the data of world and domestic clinical studies, allowing to supplement the histological characteristics of primary glioblastomas with genetic markers: the presence of the TERT mutation, EFGR amplification, loss of PTEN function, LOH 10q, and the presence of the BRAF mutation. It should be noted that the amplification of EGFR, causing resistance to apoptotic stimuli and alkylating chemotherapy with Temozolomide, attracts much attention as a therapeutic target. The frequency of occurrence of the TERT mutation is 90% of all tumors of various genesis, most often the TERT mutation is found in oligodendroglioma or primary glioblastoma. Loss of heterozygosity in the region of localization of the PTEN gene is observed in many types of sporadic tumors, including more than 40% of glioblastomas. Mutations in this gene are found in tumors of the brain, endometrium, prostate, kidney, and mammary gland. The presence of a PTEN mutation is a poor prognostic factor. LOH 22q is much more common in secondary glioblastomas (82%) than in primary glioblastomas (41%). Among brain tumors, the BRAF mutation is most common with pleomorphic xanastrocytoma (60-70%).The BRAF V600E mutation was found in epithelioid glioblastoma, which is a rare and aggressive type of glioblastoma, characterized by an unfavorable prognosis (about 6 months) and frequent leptomeningeal spread. Thus, knowledge of the molecular mechanisms of carcinogenesis will enable a personalized approach to treatment with glioblastomas of the brain.

Radiomic features of renal cell carcinoma primary and metastatic sites as predictors of TERT and BAP1 mutations.

282 Background: TERT and BAP1 mutations are associated with poor clinical outcome in patients (pts) with metastatic renal cell carcinoma (mRCC) (Dizman et al JITC 2020; Joseph et al J Urol 2016). In this study we explore radiogenomics as a non-invasive method to identify these alterations. Methods: Pts with mRCC who had genomic testing in the course of routine clinical care were included in the current analysis. Pts were assessed with the GEM Extra assay, a CAP-accredited, CLIA-certified test encompassing paired tumor-normal whole exome sequencing (WES) and tumor whole transcriptome sequencing (TGen; Phoenix, AZ). Pts underwent CT imaging; radiomic analysis was performed on the segmented metastatic and primary lesions. Features were independently correlated with TERT and BAP1 mutation status to generate Pearson correlation values (PCVs). Results: 92 pts (65:27 M: F) were included in the analysis; of these, the majority of pts (84%) had clear cell histology. Alterations in the TERT gene were seen in 12 pts. In these pts 1,325 radiomic features of the primary tissue were examined and 251 features correlated with a PCV ≥ |0.2|. Of these, 42 features were correlated with a PCV ≥ |0.3|. Highest correlation with TERT mutation was seen with Gray Level Cooccurrence Matrix (GLCM) and First Order Features (FOF). 9 pts had BAP1 mutation with 5 detected in primary tumor and 4 in metastatic sites. Analysis of primary tumor imaging yielded no significant associations between radiomic features and BAP1 mutation. However, out of approximately 1,500 radiomic features noted in metastatic sites, 111 features correlated with BAP1 mutation with a PCV ≥ 0.2. Of these, 15 features correlated with a PCV ≥ 0.3. The radiomic features with the highest correlation with BAP1mt were Gray Level Dependence Matrix (GLDM) and GLCM. Conclusions: By identifying a correlation between radiomic features of TERT mutation in primary tumors and BAP1 mutation in metastatic sites, our work may ultimately yield a non-invasive method of discerning mutational status in patents with mRCC. Efforts are ongoing to validate our findings within The Cancer Imaging Archive.

Feasibility of Evaluating the Histologic and Genetic Subtypes of WHO Grade II-IV Gliomas by Diffusion-Weighted Imaging

Background: To explore the feasibility of diffusion-weighted imaging (DWI) metrics to predict the histologic subtypes and genetic status of gliomas (e.g., IDH, MGMT, and TERT) noninvasively.Methods: One hundred and eleven patients with pathologically confirmed WHO grade II-IV gliomas were recruited retrospectively. Apparent diffusion coefficient (ADC) values were measured in solid parts of gliomas on co-registered T2-weighted images and were compared with each other in terms of WHO grading and genotypes using t-tests. Receiver operating characteristic analysis was performed to assess the diagnostic performances of ADC. Subsequently, multiple linear regression was used to find independent variables, which can directly affect ADC values. Results: The values of overall mean ADC (omADC) and normalized ADC (nADC) of high grade gliomas and IDH wildtype gliomas were lower than low grade gliomas and IDH mutated gliomas (P<0.05). nADC values showed better diagnostic performance than omADC in identifying tumor grade (AUC: 0.787 vs. 0.750) and IDH status (AUC: 0.836 vs. 0.777). ADC values had limited abilities in distinguishing TERT status (AUC=0.607 for nADC and 0.617 for omADC) and MGMT status (AUC=0.651 for nADC). Only tumor grade and IDH status were tightly associated with ADC values.Conclusion: DWI metrics can predict glioma grading and IDH mutation noninvasively, but have limited use in detecting TERT mutation and MGMT methylation.

Feasibility of Evaluating the Histologic and Genetic Subtypes of WHO Grade II-IV Gliomas by Diffusion-Weighted Imaging

Background: To explore the feasibility of diffusion-weighted imaging (DWI) metrics in order to predict the histologic subtypes and genetic status (e.g., IDH, MGMT, and TERT) of glioma noninvasively.Methods: One hundred and eleven patients with pathologically confirmed WHO grade II-IV gliomas were recruited retrospectively. Apparent diffusion coefficient (ADC) values were measured in solid parts of gliomas on co-registered T2-weighted images and were compared with each other in terms of WHO grading and genotypes using t tests. Receiver operating characteristic analysis was performed to assess the diagnostic performances of ADC. Subsequently, multiple linear regression was used to find independent variables, which can affect ADC values.Results: The values of overall mean ADC (omADC) and normalized ADC (nADC) of glioblastoma and IDH wildtype gliomas were lower than lower grade gliomas and IDH mutated gliomas (P<0.05). nADC values showed better diagnostic performance than omADC in identifying tumor grade (AUC: 0.749 vs. 0.716) and IDH status (AUC: 0.836 vs. 0.777). ADC values had limited abilities in distinguishing TERT status (AUC=0.607 for nADC and 0.617 for omADC) and MGMT status (AUC=0.651 for nADC). Only tumor grade and IDH status were tightly associated with ADC values.Conclusion: DWI metrics can predict glioma grading and IDH mutation noninvasively, but has limited use in the detection of TERT mutation and MGMT methylation.

TERT Promoter Mutation and Extent of Thyroidectomy in Patients with 1–4 cm Intrathyroidal Papillary Carcinoma

There are concerns regarding overtreatment in papillary thyroid carcinoma (PTC). BRAF V600E and TERT promoter mutations play important roles in the development of PTC. However, initial surgical approaches for PTC based on genetic characteristics remain unclear. The present study aimed to identify genetic mutations as predictors of prognosis and to establish proper indications for lobectomy (LT) in patients with 1–4 cm intrathyroidal PTC. Prospectively accumulated data from 685 consecutive patients with PTC who underwent primary thyroid surgery at the Cancer Institute Hospital, Tokyo, Japan, between 2001 and 2012 were retrospectively reviewed. Of the 685 patients examined, 538 (78.5%) had BRAF V600E mutation and 133 (19.4%) had TERT promoter mutations. Patients with TERT promoter mutations displayed significantly worse outcomes than those without mutations (10-year cause-specific survival (CSS): 73.7% vs. 98.1%, p < 0.001; 10-year disease-free survival (DFS): 53.7% vs. 93.3%, p < 0.001). As for extent of thyroidectomy among TERT mutation-negative patients with 1–4 cm intrathyroidal PTC, patients who underwent LT showed no significant differences in 10-year CSS and 10-year DFS compared to patients who had total thyroidectomy (TT) under propensity score-matching. Avoiding TT for those patients indicates a possible pathway to prevent overtreatment and reduce postoperative complications.

TERT Mutation was Associated with the Risk of Recurrence in Lung Adenocarcinoma with A Micropapillary Pattern

Background: Lung adenocarcinoma with a micropapillary pattern (MPPAC) is the histological subtype of lung cancer. It has attracted increasing attention, especially regarding its association with poor prognosis, including the predisposition towards recurrence and metastasis. Although MPPAC has been described in early-stage cases, only a few studies have reported the correlation between disease-specific prognosis and gene mutation of MPPAC. This study aimed to clarify the common genetic mutations and the prognostic characteristics in MPPAC patients.Methods: A total of 17 patients whose surgical pathology was defined as MPPAC were followed up, the molecular characteristics were elucidated by next-generation sequencing, and the prognostic characteristics were analyzed. Results: Epidermal growth factor receptor (EGFR) mutations were identified in 11/17 (65%) of patients. TP53 alterations were identified in 10/17 (59%). Other common mutations include ATM (18%), KRAS (18%), SDHA (18%), and TERT (18%). MPPAC patients harboring EGFR and TERT mutations were at a high risk of tumor recurrence, while TP53 might be associated with a low risk of recurrence. Conclusions: TERT mutation was more frequently harbored in MPPAC patients than in the other histological type of lung cancer, and such patients were at a high risk of recurrence. So TERT mutation might be associated with adverse prognosis in MPPAC patients.